Fungal infections of nails, both toe nails and finger nails, are a widespread problem, especially to people with compromised peripheral circulation such as the elderly, chronically ill, and diabetic. Others afflicted with such infections include workers in the medical field, farmers, persons with military service backgrounds, and users of acrylic nail care products. These infections are irritating and are not easily eliminated, even with repeated applications of commonly prescribed treatments.
Biologically active antimicrobial compounds have proved difficult to administer by the topical route for the treatment of mycotic (yeast, mold, and fungal) and bacterial infections of human nails and adjacent tissue. Commonly applied topical formulations such as creams, ointments, tinctures, aqueous and non-aqueous solutions and suspensions and the like are typically absorbed or rubbed off onto socks and shoes when applied to the toenails and adjacent tissue; likewise, formulations applied topically to the fingernails and adjacent tissue are typically absorbed onto clothing or gloves or rubbed off incidently during hand washing. Moreover, it has not been adequately demonstrated that the previously used topical formulations deliver therapeutically adequate doses of the biologically active antimicrobial material to the mycotic or bacterially infected tissue when applied to the nail and adjacent tissue.
Various attempts have been made to address the inadequacies of the topical administration of the antimicrobial compositions including the development of various medicating devices for the human nails and adjacent tissues. An example of such a device is set forth in U.S. Pat. No. 5,181,914 which discloses a device which occlusively covers the targeted tissue area with a bandage type device having a medication reservoir. The therapeutic efficacy of such devices markedly depends on the specific biologically active compound employed and the ability of the applied formulation to effectively deliver the active compound to the affected tissue. Furthermore, such treatment requires that the patient wear such a device throughout the treatment.
Research relating to the treatment of infections has primarily centered around the compositions used for treating the infected tissue areas. Various compositions have been developed and used by the medical industry. For example, a composition containing the water insoluble fungistatic agent undecylenic acid with the topical antiseptic agent chloroxylenol in an oil based solvent has been sold under the trade name GORDOCHOM (Gordon Laboratories, Upper Darby, Pa.). Also, a composition containing the fungistatic agent triacetin, topical antiseptic agents chloroxylenol and cetyl pyridinium chloride, alcohols, and a keratolytic agent glacial acetic acid in an aqueous tincture with several cosmetic preservatives has been sold under the name Fungoid.RTM. Tincture (PEDiNOL Pharmacal, Farmingdale N.Y.). The Fungoid.RTM. composition has also been formulated using the fungicidal agent miconazol nitrate. Further, a composition sold under the trade name FungiNail.RTM. (Kramer Laboratories, Fla.) containing a fungistatic agent undecylenic acid with a topical antiseptic agent chloroxylenol and several keratolytic agents such as acetic acid and salicylic acid in a vehicle containing alcohol and a topical anethestic agent benzocaine. Finally a further composition sold under the name Mone (Kenlor Industries, Santa Aria Calif.) containing an antimicrobial agent didecyl dioctyl ammonium chloride with several surfactants and several cosmetic preservatives in an aqueous media has also been used for the treatment of microbial infections. Several of the prior compositions contain acids, alcohols and other non-aqueous solvents which have been demonstrated to cause contact dermatitis if topical administration is chronic or in sufficiently high concentration. Further, several of the compositions containing active agents other than the quaternary ammonium compounds may be ineffective in delivering the active agent to the human nails and adjacent tissue and are thus of unproven therapeutic value.
A need therefore exists to develop an antimicrobial composition which can deliver the antimicrobial agent effectively to the site of the infection, such as an infected nail and surrounding tissue area. The antimicrobial compositions should therefore not only contain an effective antimicrobial agent but also be in a form that can effectively deliver that active agent to the infected area when administered topically.